1. Field of the Invention
The present invention relates generally to a fan bearing cup connection structure, which can enhance the connection precision between the fan bearing cup and the fan frame body and enhance the concentricity of the bearing cup and the bottom board.
2. Description of the Related Art
A conventional cooling fan is mainly used to forcedly guide airflow to dissipate the heat of a heat source. In the cooling fan, an inductive magnetization takes place between the rotor and the stator to make the rotor rotate for guiding the airflow.
In the cooling fan, the rotor has a shaft and a fan impeller assembled with the shaft. The fan impeller has a hub and multiple blades. The stator is disposed around the bearing cup of the fan frame body corresponding to the hub of the fan impeller. In general, the bearing cup of the fan is a structure body formed by injection molding and integrally connected with the fan frame body. Alternatively, the bearing cup of the cooling fan can be made of copper material. The copper-made bearing cup is connected on the base seat of the fan frame body by means of riveting. However, in the riveting process, the structure of the fan is easy to damage. Moreover, the bearing cup is apt to loosen from the base seat due to incomplete riveting to make noise. In addition, in the riveting process, a pressure is applied to the copper-made bearing cup to force the copper-made bearing cup into the base seat of the fan frame body by press fit. It is hard to control the concentricity of the copper-made bearing cup and the base seat of the fan frame body.
Furthermore, the conventional metal-made bearing cup is assembled and connected with the metal-made fan frame body. Both the bearing cup and the fan frame body are made of metal material. As a result, when the fan operates and vibrates, the metal-made bearing cup often co-vibrates with the metal-made fan frame body to make noise.
It is therefore tried by the applicant to provide a fan bearing cup connection structure to solve the above problems existing in the conventional cooling fan.